> For the complete documentation index, see [llms.txt](https://kingsznhone.gitbook.io/vsop2013.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kingsznhone.gitbook.io/vsop2013.net/vsop2013/original-readme/computation.md).

# Computation

The program VSOP2013.f (Fortran) computes the planetary elliptic elements between 1890 and 2000 using the files VSOP2013.

This program computes also the planetary rectangular coordinates referred to the dynamical ecliptic frame of J2000 and referred to the equatorial frame of ICRS.

Starting date : 1890 June 26 12h (DJ 2411545.0)

Number of dates : 11

Step : 4000 days.

The results of this computation are given in the file: VSOP2013.outThe file VSOP2013.ctl is given for checking these results.

The mean elements of the elliptic variables of the series VSOP2013 are given in the file: VSOP2013-secular.dat.

The astronomical constants consistent with the solution VSOP2013 are the constants used in the numerical integration INPOP10a, especially:

| AU      | 0.1495978706910000D+09 | km       |
| ------- | ---------------------- | -------- |
| CLIGHT  | 0.2997924580000000D+06 | m/s      |
| GM\_Mer | 0.4912547451450812D-10 | au3/day2 |
| GM\_Ven | 0.7243452486162703D-09 | au3/day2 |
| GM\_EMB | 0.8997011603631609D-09 | au3/day2 |
| GM\_Mar | 0.9549535105779258D-10 | au3/day2 |
| GM\_Ves | 0.3939673413269574D-13 | au3/day2 |
| GM\_Iri | 0.2299798032187260D-14 | au3/day2 |
| GM\_Bam | 0.1388563508297703D-14 | au3/day2 |
| GM\_Cer | 0.1408056343979966D-12 | au3/day2 |
| GM\_Pal | 0.3296275038741825D-13 | au3/day2 |
| GM\_Jup | 0.2825345842083778D-06 | au3/day2 |
| GM\_Sat | 0.8459715185680659D-07 | au3/day2 |
| GM\_Ura | 0.1292024916781969D-07 | au3/day2 |
| GM\_Nep | 0.1524358900784276D-07 | au3/day2 |
| GM\_Plu | 0.2188699765425970D-11 | au3/day2 |
| GM\_Sun | 0.2959122083684144D-03 | au3/day2 |
| EMRAT   | 0.8130056999999999D+02 |          |
| RSUN    | 0.6960000000000000D+06 | km       |
| RMOON   | 0.1738000000000000D+04 | km       |
| REARTH  | 0.6378136600000000D+04 | km       |
| J2SUN   | 0.2400000000000000D-06 |          |


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